Axial flow gas turbine engines are typically formed of a compression section, a combustion section and a turbine section. Working medium gases are drawn into the compression section where they pass through several stages of compression causing the temperature and the pressure of the gases to rise. The gases are mixed with the fuel in the combustion section and burned to form hot pressurized gases. These gases are a source of energy to the engine and are expanded through the turbine section to produce work.
In fixed wing aircraft, the engine is mounted in a housing attached to the wing of the aircraft commonly referred to as a nacelle. The nacelle both supports and positions the engine with respect to the aircraft. An electrical generator driven by the engine for supplying electric power to the aircraft is located within the nacelle. The production of electric power is accompanied by the production of heat which must be removed to preserve the operating life of the generator. This heat may be removed by lubricating oil passing through the generator. A construction using lubricating oil as the means for removing heat is shown in U.S. Pat. No. 4,151,710 entitled "Lubrication Cooling System for Aircraft Engine Accessory" issued to Griffin et al. The heat is rejected primarily to a heat exchanger extending into a flow path of the engine and secondarily to a heat exchanger in communication with fuel being flowed to the combustion chambers.
Notwithstanding the availability of the above systems, scientists and engineers continue to seek yet improved cooling systems which have minimal adverse effect upon the efficiency of the operating engine.